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Neutrinos may acquire dark moments via one-loop effects of dark photon and new light particles in the loop. Due to the kinetic mixing between the dark photon and the Standard Model photon, neutrinos would obtain effective electromagnetic moments. We focus on probing these neutrino moments through superradiance of black holes. Black hole superradiance can be quenched through fermionic pair production from the bosonic cloud. We consider the production of dark photons from black hole superradiance and quenching occurs through the production of neutrino-antineutrino pairs from the dark photons. The efficiency of the pair production depends on the effective coupling between the photons and neutrinos, i.e., the electromagnetic moments. We show that for certain benchmark parameters, this neutrino-dark photon coupling could lead to observable neutrino fluxes in the ultra-high energy regime. We also discuss bounds on primordial black hole abundance from neutrino background arising from such a quenched superradiance mechanism.